This application is related to United States Patent Applications entitled A SYSTEM, METHOD AND ARTICLE OF MANUFACTURE FOR A DEVELOPMENT ARCHITECTURE FRAMEWORK and A SYSTEM, METHOD AND ARTICLE OF MANUFACTURE FOR MAINTENANCE AND ADMINISTRATION IN AN E-COMMERCE APPLICATION FRAMEWORK, both of which are filed concurrently herewith and which are incorporated by reference in their entirety.
The present invention relates to error handling and more particularly to testing successfulness of an operation.
An important use of computers is the transfer of information over a network. Currently, the largest computer network in existence is the Internet. The Internet is a worldwide interconnection of computer networks that communicate using a common protocol. Millions of computers, from low end personal computers to high-end super computers are coupled to the Internet.
The Internet grew out of work funded in the 1960s by the U.S. Defense Department""s Advanced Research Projects Agency. For a long time, Internet was used by researchers in universities and national laboratories to share information. As the existence of the Internet became more widely known, many users outside of the academic/research community (e.g., employees of large corporations) started to use Internet to carry electronic mail.
In 1989, a new type of information system known as the World-Wide-Web (xe2x80x9cthe Webxe2x80x9d) was introduced to the Internet. Early development of the Web took place at CERN, the European Particle Physics Laboratory. The Web is a wide-area hypermedia information retrieval system aimed to give wide access to a large universe of documents. At that time, the Web was known to and used by the academic/research community only. There was no easily available tool which allows a technically untrained person to access the Web.
In 1993, researchers at the National Center for Supercomputing Applications (NCSA) released a Web browser called xe2x80x9cMosaicxe2x80x9d that implemented a graphical user interface (GUI). Mosaic""s graphical user interface was simple to learn yet powerful. The Mosaic browser allows a user to retrieve documents from the World-Wide-Web using simple point-and-click commands. Because the user does not have to be technically trained and the browser is pleasant to use, it has the potential of opening up the Internet to the masses.
The architecture of the Web follows a conventional client-server model. The terms xe2x80x9cclientxe2x80x9d and xe2x80x9cserverxe2x80x9d are used to refer to a computer""s general role as a requester of data (the client) or provider of data (the server). Under the Web environment, Web browsers reside in clients and Web documents reside in servers. Web clients and Web servers communicate using a protocol called xe2x80x9cHyperText Transfer Protocolxe2x80x9d (HTTP). A browser opens a connection to a server and initiates a request for a document. The server delivers the requested document, typically in the form of a text document coded in a standard Hypertext Markup Language (HTML) format, and when the connection is closed in the above interaction, the server serves a passive role, i.e., it accepts commands from the client and cannot request the client to perform any action.
The communication model under the conventional Web environment provides a very limited level of interaction between clients and servers. In many systems, increasing the level of interaction between components in the systems often makes the systems more robust, but increasing the interaction increases the complexity of the interaction and typically slows the rate of the interaction. Thus, the conventional Web environment provides less complex, faster interactions because of the Web""s level of interaction between clients and servers.
A system and method are provided for testing successfulness of an operation having pre-conditions and post-conditions that must be satisfied for the operation to be successful. Two types of assertion classes are provided, where one of the of the assertion classes implements assertion-checking logic and the other assertion class implements only null operations, and one of the assertion classes is selected to be raised. A first assertion is raised asserting a pre-condition that must evaluate to true if the operation is successful. The operation is then executed. A second assertion is raised asserting a post-condition that must evaluate to true if the operation is successful. An error message is outputted upon failure of at least one of the assertions, where the failed assertion implements assertion-checking logic.
In one embodiment of the present invention, an error handler may be provided for detecting a failure of the assertion of one of the conditions and shutting down a system running the operation upon the detection of the failure. In another embodiment of the present invention, an assertion may be raised at the beginning and end of every operation of a plurality of operations. Also, a check may be performed prior to raising the assertions for determining the propriety of raising the assertions.
In an aspect of the present invention, each assertion may be raised with descriptions for helping to identify where the assertion failed. In another aspect of the present invention, each assertion may be raised with parameters for helping to identify why the assertion failed.